1. Field of the Invention
The present invention relates to wireless telephones, and more particularly, to a system and method for enabling safe hands-free operation of a wireless telephone in a vehicle.
2. Background of the Invention
It has been reported that using a wireless telephone while driving is a major cause of traffic accidents. Drivers who must keep their wireless telephones close to their ears are unable to keep both hands on the steering wheels. Many governments are enacting laws that regulate the use of wireless telephones in moving vehicles.
Efforts have been made to enable drivers to use their wireless telephones in a “hands-free” mode. One such effort is described in U.S. Pat. No. 5,867,794, which was granted to Hayes et al. on Feb. 2, 1999 (the “'794 patent”). The '794 patent discloses a wireless telephone communication device that can be operated in a hands-free mode with received audio signals being relayed to the vehicle's radio for output on the speakers of the vehicle's radio. Basically, the device re-transmits the received audio using an FM frequency that is received and reproduced by the radio of the vehicle. The '794 patent is incorporated herein by reference in its entirety.
As described below, the present invention relies on pinpointing the location of the wireless telephone relative to the vehicle. The Federal Communications Commission (FCC) has promulgated new rules related to emergency call processing. The FCC's wireless Enhanced 911 (E911) rules require certain Commercial Mobile Radio Services (CMRS) carriers to begin transmission of enhanced location and identity information in two phases. The first phase, which began on Apr. 1, 1998, required wireless service providers to transmit a 911 caller's number and section of the cell site from which the call is originated to a public safety answering point (PSAP). The second phase, scheduled to begin on Oct. 31, 2001, requires all wireless service providers to locate two-thirds of all 911 callers within 125 meters of their physical locations. In other words, for all 911 calls received, a PSAP must be able to pinpoint 67% of the callers within 125 meters. It is expected that location tracking technologies to be utilized to implement E911 are likely to have greater accuracy than that required by the FCC.
Under the FCC rules, wireless communication networks and wireless telephones (or any wireless devices that can be used to call 911), must provide both the identity and location of the caller to a 911 dispatcher. To provide a caller's identity, the wireless device will furnish a device identification, e.g., a mobile identification number (MIN), indicating in most instances the telephone number of the device. To provide a caller's location, the wireless communication networks and wireless devices will use a network-based location system or a handheld location system installed within the wireless devices, or a combination of the two systems. An example of a handheld location system is a Global Positioning System (GPS) receiver. U.S. Pat. No. 5,663,734, which is incorporated herein by reference, discloses a GPS receiver and a method for processing GPS signals.